SAN FRANCISCO, March 14 (Xinhua) -- Pi, the ratio of a circle's circumference to its diameter, has been calculated out to 31.4 trillion digits and one of Google's employees has broken the world record because of this, Google said on Pi Day which fell on Thursday this year.

The employee, Emma Haruka Iwao has spent four months on the project, using 25 Google Cloud virtual machines to generate the number, which is the first time that a publicly available cloud software has been used for pi calculation. She finally calculated 31,415,926,535,897 digits of pi, beating the previous record in 2016 of nearly 9 trillion digits.

"It was my childhood dream, a longtime dream, to break the world record for pi," Iwao told CNN Business. She has been working on it since she was 12, when she first downloaded software to calculate the number on her personal computer in Japan.

Iwao's team used a program called "ycruncher" for the record-breaking result, which requires a lot of storage and memory to calculate, about the same amount of data as the entire Library of Congress print collection, Google said.

The snapshots of Iwao's calculations were saved on external discs in Google Cloud, which means that all the new digits of pi calculation can be downloaded by anyone who wants to experiment with the data.

Because of its complexity and irrationality, pi is often used by developers and programmers to test the performance of new hardware or cloud computing. The new record shows how far cloud computing technology could go.